/**
 *
 * Ashish Patel
 * e: ashishsushilPatel@gmail.com
 * w: https://ashish.me
 *
 */

function TreeNode(val, children) {
  this.val = val
  this.children = children
}

const maximumDepthOfTree = root => {
  let max = 0
  if (root == null) {
    return max
  }
  const levelOrderTraversal = (root, level) => {
    if (root && root.children && root.children.length) {
      for (let i = 0; i < root.children.length; i++) {
        levelOrderTraversal(root.children[i], level + 1)
      }
    } else {
      if (level > max) {
        max = level
      }
    }
  }
  levelOrderTraversal(root, 1)
  return max
}

test('maximumDepthOfTree', () => {
  const t1 = new TreeNode(1)
  t1.children = [new TreeNode(3, [new TreeNode(5), new TreeNode(6)]), new TreeNode(2), new TreeNode(4)]
  expect(maximumDepthOfTree(t1)).toEqual(3)
})